An airway tube system, such as an endotracheal tube (ETT) system, may include an inflatable cuff around an ETT of the ETT system for positioning the ETT in an airway of a patient and sealing the airway of the patient. For example, when the ETT is positioned in a patient, the inflatable cuff may be inflated to contact the airway wall of the patient in order to form a seal with the airway of the patient. This seal formed between the airway wall of the patient and the inflatable cuff may be beneficial for preventing aspiration, such as macroaspiration and microaspiration, of secretions of the intubated and ventilated patients, in at least one example. It is noted that reference to secretions herein may refer to bodily fluids of a patient, such sputum or mucus, for example. Additionally, sealing the airway of the patient may help to prevent objects foreign to the body of the patient from traveling down the airway of the patient.
However, it is very difficult to obtain a complete seal between the inflatable cuff and the airway wall of a patient, and in such examples where the inflatable cuff and the airway wall of the patient are not completely sealed, secretions of intubated and ventilated patients may accumulate upstream the inflatable cuff and leak dowsntream the inflatable cuff and into a bronchial tree and lungs of the patient. The leakage of secretions into the bronchial tree and lungs may then potentially lead to undesirable biofilm formation, and, in some cases, develop into ventilation-associated pneumonia (VAP).
Specifically in a case of an ETT system, the shaping of many inflatable cuffs may be too round to form sufficient sealing with the trachea to prevent leakage of secretions past an inflatable cuff of the ETT system, as the trachea varies in shape from top to bottom. Further, the trachea varies in deformability from an anterior wall of the trachea that has cartilage to a posterior wall of the trachea comprising soft tissue posing further challenges to forming sufficient sealing between the inflatable cuff and the trachea. Thus, secretions may leak past the inflatable cuff via regions between the inflatable cuff and the trachea wall and into the bronchial tree and lungs of the patient due to the trachea wall variation in shape and rigidity preventing the inflatable cuff from forming a sufficient seal.
Previous approaches to address the above problems may have included varying a shape of the cuff to better seal the airway and collect the secretions. For example, previous approaches may have included attaching reinforcement material on an inside of the cuff to restrict a portion of the cuff for shaping purposes. Further, previous approaches may have also included molding the inflatable cuff, so that the inflatable cuff includes one or more restricted portions upon inflation of the inflatable cuff.
Additionally, other previous approaches may have included the use of multiple cuffs to form multiple seals between the ETT system and the airway of the patient, such as taught in US 2009/0032027 A1. Thus, secretions which may leak past a first cuff may be trapped between the first cuff and a second cuff, rather than the secretions draining into a bronchial tree and lungs of a patient.
However, the inventors have recognized several problems with the above approaches. For example, approaches that include attachment of reinforcement material to an interior of an inflatable cuff to shape the inflatable cuff, that mold the inflatable cuff to include one or more restricted portions, and that use a plurality of separate cuffs to improve sealing of the airway may be complex to produce. Further, as these approaches for shaping the inflatable cuff are complex to produce, a number of valleys and a positioning of the valleys may be difficult to alter in a case where patient require such adjustments to prevent aspiration of secretions during intubation. Moreover, these previous approaches fail to include robust drainage systems to remove trapped secretions.
Thus, recognizing the above problems, the inventors herein have developed an ETT system for collecting and draining secretions, so that aspiration of such secretions may be prevented. Additionally, the ETT system developed by the inventors may prevent aspiration of foreign objects, such as debris that may enter the airway while a patient is intubated, for example.
In at least one example, the ETT system developed by the inventors includes an inflatable cuff surrounding a tube (i.e., ETT), and a restrictor including one or more cavities, the restrictor surrounding an outer surface of the inflatable cuff, such that the inflatable cuff is positioned between the restrictor and the tube. The restrictor may restrict the inflatable cuff to form a valley region of the inflatable cuff that positioned between protruding regions of the inflatable cuff when the inflatable cuff is in an inflated state, and a drainage assembly may be coupled to the restrictor in at least one example.
The above ETT system developed by the inventors achieves several advantages. For example, when the above described ETT of the ETT system is positioned in a trachea of a patient and in the inflated state, the protruding regions of the inflatable cuff may contact the trachea wall of the patient to form at least upper and lower seal segments, while the valley formed between the protruding regions may not contact the trachea wall of the patient. Put another way, the protruding regions of the inflatable cuff may form sealed regions with the trachea wall of the patient, while the valley of the inflatable cuff may form an unsealed region with the trachea wall of the patient, where a sealed region is a region of contact between the trachea wall of the patient and the inflatable cuff. An unsealed region positioned between two sealed regions of the ETT system when the ETT system is in the inflated state and positioned in a patient enables collection of secretions at the unsealed region. The secretions collected at the collection region formed at the unsealed region may then be drained via suction of the collected secretions through the one or more cavities formed into the restrictor via a drainage bulb coupled to the restrictor.
For example, the secretions collected at the collection region may be removed via a restrictor drainage assembly that utilizes active suctioning of the collected secretions to move the collected secretions through one or more cavities formed in the restrictor, through a restrictor drainage line, and into a collection reservoir of a restrictor drainage bulb.
Thus, the above approach developed by the inventors may better prevent aspiration compared to traditional approaches, as the above approach may both collect and drain secretions in a robust manner. Benefits in regards to qualifying and sampling the collected secretions for laboratory studies may also be realized. Furthermore, the drainage bulb suction pressure applied to the unsealed region that is positioned between the sealed regions advantageously enables monitoring of a quality of both the upper and lower balloon seals. Thus, potential balloon malfunctions following placement of the ETT system in a patient may be detected and addressed. Moreover, the simplicity of the ETT system developed by the inventors may reduce a cost for manufacturing the ETT system compared to previous approaches.